pszKey (PSZ) - input
The name of the key for which the profile data is required. The name must match exactly with the name stored in the profile. There is no case-independent searching.
If this parameter is NULL, and if pszApp is not equal to NULL, this call enumerates all key names associated with the named application and returns the key names, but not their values, as a list in the pBuffer parameter. Each key name is terminated with a NULL character and the last name is terminated with two successive NULL characters. In this case, the pulBufferMax parameter contains the total length of the list excluding the final NULL character.